Suspicious Flax Typhoon Network Level Authentication Disabled via Registry (via registry_set)

PremiumReviewedSigma · Medium · v1
Product
windows
Category
registry_set
Author
HuntRule
Published
2026-10-15
Updated
2026-10-15

ATT&CK techniques

Persistence → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects disabling of Network Level Authentication for RDP by setting the UserAuthentication value to 0 under the RDP-Tcp terminal server key. Flax Typhoon disabled NLA to weaken RDP protections and enable the Sticky Keys logon-screen hijack for remote access.

Related detections9 linkedT1112 — drag to rearrange
Suspicious Access to Chrome Encrypted Preference MAC Registry Values (via registry_set)
Suspicious Deletion of Terminal Server Client History via reg by UNC1549
Suspicious Registry Class Key Creation for COLDRIVER Persistence
Suspicious Modification of CloudFiles BlockedApps Policy via registry_set
Suspicious Disabling of Malicious Software Removal Tool via registry_set
Suspicious SmartScreen Disable via Registry Modification via registry_set
Suspicious HrServ Registry Command Channel under IdentityStore RemoteFile (via registry_set)
Malicious Microsoft Defender Disable via Registry by Key Group
Suspicious PowerShell Decoding Base64 Payload Stored in Registry
Suspicious Flax Typhoon Network Level Authentication Disabled via Registry (via registry_set)
Pivot detection · T1112 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.